A low-toxicity drug will be developed to reduce or eliminate the cardiotoxicity associated with adriamycin cancer chemotherapy. Compounds which are being synthesized and studied are persistent carbon free radicals which are scavengers of reactive free radicals and capable of reducing peroxides. As part of the development of the drug a structure reactivity relationship for the free radicals will be established. New electronically and sterically stabilized radicals will be synthesized. Substituents will also be incorporated to achieve water and/or lipid solubility.